Studies on the metabolic fate of drugs and their biochemical effects in animals and man are being pursued in order to relate pharmacological action to molecular events and clinical efficacy. Work in progress includes determination of the mode of action of bromocryptine in animals, synthesis and chronic testing of 4-phenyl-4-propionoxy-N-methylpiperidine and related compounds in animals, imipramine and desipramine levels in various patient groups, and the pharmacokinetics of cocaine in humans. BIBLIOGRAPHIC REFERENCE: Claeys, M., Markey, S.P., and Maenhaut, W.: Variance analysis of error in selected ion monitoring assays using various internal standards. A practical study case. Biomed. Mass Spectrom. 4: 122-128, 1977.